1. Field of the Invention
The present invention relates generally to anionic surfactant compositions and, more particularly, to anionic surfactant compositions containing alkoxylated amine surfactants, such as ethoxylated amines and/or ethoxylated ether amines, and having enhanced detergent performance.
2. Description of Related Art
Multiple surfactants in formulated laundry detergents are often employed. For example, anionic surfactants have been found to give good performance on polar types of soils and help to prevent soil redeposition. Nonionic surfactants have been found to give good detergency on nonpolar soils and have better hard water tolerance.
Typical anionic surfactants used in laundry include, but are not limited to, linear alkyl benzene sulfonates, alkyl sulfates, ether sulfates, secondary alkyl sulfates, xcex1-olefin sulfonate, phosphate esters, sulfosuccinates, isethionates, carboxylates, etc. Most of these surfactants are typically sold in the form of a sodium salt.
One common type of anionic surfactant, linear alkylbenzene sulfonate (xe2x80x9cLASxe2x80x9d), is widely used in commercial cleanser products due to its effectiveness as a detergent, ease of biodegradation, and relative low cost. Typically, linear alkylbenzene sulfonates are produced via sulfonation of linear alkylbenzene intermediates.
Linear alkylbenzene is typically manufactured on an industrial scale using one of three commercial processes which differ from one another primarily by virtue of the catalyst system employed. In this regard, one process employs an aluminum trichloride catalyst, another process uses a hydrogen fluoride catalyst while the third process uses solid alkylation catalyst. The three processes result in linear alkylbenzene products with different phenyl isomer distributions. For example, a typical phenyl isomer distribution for products of the aluminum trichloride process is about 30% 2-phenyl isomer and about 22% 3-phenyl isomer. In contrast, a typical phenyl isomer distribution for products of the hydrogen fluoride process is about 20% 2-phenyl isomer and about 20% 3-phenyl isomer, although reported values may differ. The product of the aluminum trichloride process, which is relatively high in 2-phenyl isomer content, is often referred to as xe2x80x9chigh 2-phenylxe2x80x9d linear alkylbenzene, whereas the product of the hydrogen fluoride process, which is relatively low in 2-phenyl isomer content, is often referred to as xe2x80x9clow 2-phenylxe2x80x9d linear alkylbenzene.
The sulfonates of linear alkylbenzenes are known to exhibit different physical properties depending upon the position of the aromatic group on the alkyl chain. Therefore, high 2-phenyl linear alkylbenzene sulfonates have physical properties that differ from low 2-phenyl linear alkylbenzene sulfonates. For example, high 2-phenyl linear alkylbenzene sulfonates typically have a higher solubility in aqueous media than do low 2-phenyl linear alkylbenzene sulfonates. Furthermore, an aqueous solution comprising a high 2-phenyl linear alkylbenzene sulfonate may exhibit a higher viscosity than an aqueous solution comprising a low 2-phenyl linear alkylbenzene sulfonate. In cases where maximum solubility of linear alkylbenzene sulfonate in an aqueous detergent formulation is of concern, a product containing a relatively high percentage of compounds in which the aromatic substituent is in the 2 or 3 position and a correspondingly smaller percentage of isomers in which the aromatic substituent is positioned centrally with respect to the alkyl chain may be advantageous.
Hydrotropes, such as sodium xylene sulfonate, may be added to improve solubility of low 2-phenyl linear alkylbenzene sulfonates. As used herein, the term xe2x80x9chydrotropexe2x80x9d is defined to be a compound that has the property of increasing the aqueous solubility of various slightly soluble organic chemicals.
Disclosed herein are improved surfactant compositions. Surprisingly, detergent performance of the disclosed surfactant compositions is enhanced by utilizing ethoxylated amine surfactants to supply the cation of a salt of an anionic surfactant. The disclosed surfactant compositions may be advantageously employed for a number of uses including the formulation of any surfactant or detergent composition in which one or more anionic surfactant/s are present as a surfactant component. Examples include, but are not limited to, in the formulation of heavy duty laundry detergents, herbicide emulsifiers, hard surface cleaners, bathroom cleaners, all purpose cleaners, car wash detergents, janitorial cleaners and light duty liquid detergents.
In one respect, disclosed is a surfactant composition, including at least one anionic surfactant, and at least one ethoxylated surfactant, the ethoxylated surfactant being present in an amount greater than 15% of the surfactant actives by weight, and being at least one of ethoxylated amine, ethoxylated ether amine, or a mixture thereof. In this embodiment, other components are optional, and may or may not be present. For example, the surfactant composition may further include water. The composition may also include a neutralizing compound, the neutralizing compound being at least one of alkanolamine, alkylamine, ammonium hydroxide, NaOH, KOH, or a mixture thereof. In this regard, an alkanolamine may include at least one of monoethanolamine (xe2x80x9cMEAxe2x80x9d), diethanol amine (xe2x80x9cDEAxe2x80x9d), triethanol amine (xe2x80x9cTEAxe2x80x9d), or a mixture thereof. An anionic surfactant may include at least one of alkyl benzene sulfonate, alkyl sulfate, ether sulfate, secondary alkyl sulfate, xcex1-olefin sulfonate, phosphate ester, sulfosuccinate, isethionate, carboxylate, or a mixture thereof. An ethoxylated amine surfactant may include at least one of ethoxylated primary, secondary or tertiary amine, or a mixture thereof. An ethoxylated tertiary amine surfactant may have the formula: 
wherein: R=straight or branched alkyl group having from about 8 to about 22 carbon atoms;
n=moles of ethoxylation and is from about 2 to about 50; and
x=from about 1 to about 49.
Alternatively, in the preceding embodiment, n may be from about 2 to about 30 and x may be from about 1 to about 29.
An ethoxylated amine surfactant may be a tallow-amine-ethoxylate having the formula: 
wherein: R=straight or branched alkyl group having from about 16 to about 18 carbon atoms;
n=moles of ethoxylation and is from about 5 to about 20; and
x=from about 4 to about 19.
An ethoxylated ether amine surfactant may have the formula: 
wherein: R=straight or branched alkyl group having from about 8 to about 18 carbon atoms;
n=moles of ethoxylation and is from about 2 to about 30; and
x=from about 1 to about 29; and
y=1 to 30.
Alternatively, in the preceding embodiment, n may be from about 2 to about 50 and x may be from about 1 to about 49.
In another respect, disclosed is a surfactant composition, including: from about 8% to about 35% of the surfactant actives by weight of an anionic surfactant, wherein the anionic surfactant includes at least one of alkyl benzene sulfonate, alkyl sulfate, ether sulfate, secondary alkyl sulfate, xcex1-olefin sulfonates, phosphate esters, sulfosuccinates, isethionates, carboxylates, or a mixture thereof; from about 8% to about 35% of the surfactant actives by weight of an ethoxylated surfactant, wherein the ethoxylated surfactant is at least one of ethoxylated amine, ethoxylated ether amine, or a mixture thereof; from about 15% to about 55% of the surfactant actives by weight of a nonionic surfactant, wherein the nonionic surfactant includes at least one of nonylphenol ethoxylate, alcohol ethoxylate, ethylene oxide/propylene oxide block copolymer, or a mixture thereof; from about 10% to about 90% water by weight of total weight of the composition; and from about 0% to about 9% neutralizing compound by weight of total weight of the composition, wherein the neutralizing compound includes at least one of alkanolamine, alkylamine, ammonium hydroxide, sodium hydroxide, potassium hydroxide, or mixture thereof; and wherein the total active surfactant concentration is from about 10% to about 90% by weight of total weight of the composition. The alkanolamine may include at least one of monoethanolamine, DEA, TEA, or a mixture thereof. The anionic surfactant may include at least one of alkyl benzene sulfonate, alkyl sulfate, ether sulfate, secondary alkyl sulfate, xcex1-olefin sulfonates, phosphate esters, sulfosuccinates, isethionates, carboxylates, or a mixture thereof. The ethoxylated amine surfactant may include at least one of ethoxylated primary, secondary or tertiary amine, or a mixture thereof. The ethoxylated amine surfactant may be a tertiary amine having the formula: 
wherein: R=straight or branched alkyl group having from about 8 to about 22 carbon atoms;
n=moles of ethoxylation and is from about 2 to about 50; and
x=from about 1 to about 49.
Alternatively, in the preceding embodiment, n may be from about 2 to about 30 and x may be from about 1 to about 29.
The ethoxylated amine surfactant may be a tallow-amine-ethoxylate having the formula: 
wherein: R=straight or branched alkyl group having from about 16 to about 18 carbon atoms;
n=moles of ethoxylation and is from about 5 to about 20; and
x=from about 4 to about 19.
The nonionic surfactant may include at least one of nonylphenol ethoxylate, alcohol ethoxylate or EOxe2x80x94PO block copolymer, or a mixture thereof.
In another respect, disclosed is a surfactant composition, including anionic surfactant; and greater than 15% of surfactant actives by weight of an alkoxylated tertiary amine surfactant. The surfactant composition may include from 15% to about 35% of surfactant actives by weight alkoxylated tertiary amine surfactant, alternatively from about 17% to about 35% of the surfactant actives by weight alkoxylated tertiary amine surfactant alternatively from about 20% to about 35% of surfactant actives by weight alkoxylated tertiary amine surfactant. The surfactant composition may alternatively include greater than about 17% of surfactant actives by weight alkoxylated tertiary amine surfactant, alternatively from about 20% to about 35% of surfactant actives by weight alkoxylated tertiary amine surfactant. Further alternatively the composition may include individual respective ranges of weight percentage values greater than each respective integer defined between 15 and 35%, or alternatively individual respective ranges of weight percentage values between 35% and each respective integer defined between 15% and 34%.
In another respect, disclosed is a surfactant composition, including at least one anionic surfactant; and greater than 15% of the surfactant actives by weight alkoxylated tertiary amine surfactant. In this embodiment, other components are optional, and may or may not be present. The composition may include from 15% to about 50% of the surfactant actives by weight alkoxylated tertiary amine surfactant.
In another respect, disclosed is a surfactant composition, including at least one anionic surfactant, at least one alkoxylated surfactant, at least one nonionic surfactant, propylene glycol, at least one neutralizing compound, and substantially no water, and wherein the components are present in amounts such that the surfactant solution exists as a substantially homogenous liquid phase at a temperature of about 40xc2x0 F. Thus, using the disclosed method a surfactant composition that exists as a substantially homogenous liquid solution (or as a solution of substantially uniformly dispersed components) at about 40xc2x0 F. may be formulated from effective amounts of: anionic surfactant; alkoxylated surfactant; optional nonionic surfactant; polyethylene glycol; optional neutralizing compound, and substantially no water. Water or aqueous solvent may be optionally added, however.
As used herein, the indefinite articles xe2x80x9caxe2x80x9d and xe2x80x9canxe2x80x9d connote xe2x80x9cone or more.xe2x80x9d When individual active surfactant concentrations are expressed herein for a surfactant composition as a percentage of the surfactant actives by weight, it refers to the weight of a given surfactant actives expressed as a percentage of the total weight of all surfactants actives present in the given composition, excluding any non-surfactant components. For those compositions made up of 100% active surfactant materials, the weight percentage of a given component expressed as a percentage of surfactant actives would be the same as the weight percentage expressed as a percentage of the total weight of the composition.
In the following description, Tables 1-12 are referred to with regard to specific commercial and exemplary components which may be employed in various combinations in the formulation of the disclosed surfactant compositions. With benefit of this disclosure it will be understood by those of skill in the art that any of the specific compounds, and/or combinations thereof, disclosed in these tables may be employed to the extent they are suitable for use in any of the embodiments disclosed herein, whether otherwise specifically referred to or not.
In the formulation of the disclosed surfactant compositions, ethoxylated amine surfactants may be combined with salts or acids of anionic surfactants to form salts between the ethoxylated amine surfactants and the anionic surfactants. Such salts may be formed, for example, via exchange of amine and sodium cations.
A range of alkoxylated amine surfactants may be used to form the salt. Suitable alkoxylated amines include any ethoxylated amines capable of forming a water soluble salt with an anionic surfactant. Examples include primary, secondary and tertiary alkoxylated amines, ethoxylate ether amines, as well as mixtures thereof.
In one embodiment, suitable tertiary alkoxylated amine surfactants consist of a hydrocarbon tail attached to a nitrogen atom. The nitrogen atom has been alkoxylated to give tertiary amine. In one example, the tertiary amine is capable of abstracting a proton from a strong acid to form a salt. The following structure illustrates such a salt formed between an LAS acid and a tertiary ethoxylated amine: 
wherein: R=straight or branched alkyl group having from about 8 to about 22 carbon atoms;
n=total moles of ethoxylation and is from about 2 to about 30; and
x=from about 1 to about 29.
In one particular example of this embodiment, an ethoxylated amine may be a tertiary tallow amine ethoxylate in which R=straight or branched alkyl group having from about 16 to about 18 carbon atoms; n=from about 5 to about 20; and x=from about 4 to about 19.
In one particular example of this embodiment, an ethoxylated amine may be a tertiary tallow amine ethoxylate in which R=straight or branched alkyl group having from about 16 to about 18 carbon atoms; n=from about 5 to about 20; and x=from about 4 to about 19. Still other examples of suitable ethoxylated tertiary amines include ethoxylated tertiary amines having some propylene oxide or other alkoxide content. For example, xe2x80x9cRxe2x80x9d in the previously given tertiary ethoxylated amine formula may be an alkyl group as defined above, or alternatively, a combination of an alkyl group as defined above and an alkoxide group, with the alkyl group being bound to the nitrogen atom. In another example, xe2x80x9cRxe2x80x9d in the preceding tertiary amine formula may be a combination of an alkyl group as defined above and an alkylaryl, with the alkyl group being bound to the nitrogen atom. In yet another embodiment, an alkoxylated tertiary amine may be of the above formula, with the exception that one or more of the x and/or (n-x) ethylene oxide groups may be replaced with one or more propylene oxide groups, other alkylene oxide groups, or mixtures thereof.
Specific examples of suitable ethoxylated tertiary amines may also be found in Table 1.
As shown in Table 1, specific examples of suitable ethoxylated amines include, but are not limited to, ethoxylated amines of the xe2x80x9cSURFONIC(copyright)xe2x80x9d series available from Huntsman including, but not limited to, T-2, T-5, T-10, T-15, T-20, and T-50, wherein the numerical suffix indicates moles of ethoxylation per molecule. These tallow-amine-ethoxylates are of the type that may be represented by the formula: 
wherein: R=straight or branched alkyl group having from about 16 to about 18 carbon atoms;
n=moles of ethoxylation and is equivalent to the numerical suffix following the xe2x80x9cTxe2x80x9d (i.e., 2, 5, 10, 15, 20, 50, etc.); and
x and (n-x) represent number of ethylene oxide groups in separate chains on the molecule.
Examples of other suitable alkoxylated tertiary amines may be found in Table 2.
Other examples of specific suitable ethoxylated tertiary amines include, but are not limited to, Varonic T-215 available from Witco Corporation, Greenwich, Conn. and compositions available from Akzo Nobel.
Similar salts may be formed between anionic surfactants and alkoxylated secondary amines, such as ethoxylated amines having the following formula: 
wherein: R=straight or branched alkyl group having from about 8 to about 22 carbon atoms;
x=from about 1 to about 30.
In one particular example of this embodiment, an ethoxylated amine may be a secondary tallow amine ethoxylate in which R=straight or branched alkyl group having from about 16 to about 18 carbon atoms; and x=from about 5 to about 20.
In general, the secondary amine ethoxylates are present in small amount in the tertiary amine ethoxylates and may not be sold separately as commercial products.
Similar salts may be formed between anionic surfactants and ethoxylated primary amines having the following formula: 
wherein: x=from about 1 to about 30.
In one particular example of this embodiment, a primary ethoxylated amine may be one in which x=from about 2 to about 20. Examples include, but are not limited to, DIGLYCOLAMINE(trademark)xe2x80x9d available from Huntsman (2-(2-aminoethoxy) ethanol).
It will be understood with benefit of this disclosure by those of skill in the art that specific types and molecular weights of amines may be selected to fit particular purposes. For example, relatively shorter chain tertiary amine ethoxylates, like Huntsman T-2 and T-5, may be used to improve mineral oil detergency (e.g., motor oil, grease, etc.), while relatively longer chain tertiary amine ethoxylates, like Huntsman T-10 and T-15, may be used to improve trigylceride detergency (e.g., cooking oils, fats, etc.).
Alkoxylated ether amines (such as ethoxylated ether amine) surfactants may also be used, and include those having the following formula: 
wherein: R=straight or branched alkyl group having from about 8 to about 22 carbon atoms;
n=total moles of ethoxylation and is from about 2 to about 30; and
x=from about 1 to about 29; and
y=1 to 30.
In one particular example of this embodiment, an ethoxylated amine may be a tertiary tallow amine ethoxylate in which R=straight or branched alkyl group having from about 12 to about 14 carbon atoms; n=from about 5 to about 20; and x=from about 4 to about 19; and y=1 to about 20.
Specific examples of suitable alkoxylated ether amines (such as ethoxylated ether amines) etc., may be found in Tables 3 and 4. Such amines may be primary, secondary or tertiary ethoxylated ether amines. Examples include, but are not limited to, ethoxylated ether amines of the xe2x80x9cSurfonic PEA(trademark)xe2x80x9d series available from Huntsman Corporation including, but not limited to, xe2x80x9cSurfonic PEA-25(trademark)xe2x80x9d ethoxylated linear polyetheramine, wherein the two digits of the numerical suffix indicates the moles of propoxylation and ethoxylation per molecule respectively. As shown in Table 4, other examples of suitable ethoxylated ether amines include, but are not limited to, E-17-5 available from Tomah Products, Milton, Wis.
As shown in Table 3, specific examples of suitable ethoxylated ether amines include, but are not limited to, an ethoxylated ether amine of the xe2x80x9cSURFONIC(copyright)xe2x80x9d series available from Huntsman known as xe2x80x9cPEA-25xe2x80x9d, wherein the numerical suffices indicate moles of propoxylation and ethoxylation, respectively, per molecule. These ethoxylated amines are of the type that may be represented by the formula: 
wherein: R=straight or branched alkyl group having from about 12 to about 14 carbon atoms;
n=total moles of ethoxylation and is equivalent to the second numerical suffix (5 for xe2x80x9cPEA-25xe2x80x9d);
y=total moles of propoxylation and is equivalent to the first numerical suffix (2 for xe2x80x9cPEA-25xe2x80x9d); and
x and (n-x) represent number of ethylene oxide groups in separate chains on the molecule.
In one embodiment, an amount of an ethoxylated surfactant (such as ethoxylated amine and/or ethoxylated ether amine) sufficient or effective to neutralize the acid functionality of the anionic surfactant is employed, although greater or lesser amounts are also possible. The total amount of surfactant actives present in a surfactant composition may be any effective or suitable amount to form a concentrated or diluted surfactant composition. In one embodiment, the total amount of surfactant actives may range from about 1% to about 100% by weight of the total weight of the composition, alternatively from about 10% to about 100% by weight of the total weight of the composition, alternatively from about 10% to about 90% by weight of the total weight of the composition.
In exemplary embodiments, ethoxylated amine (either a single ethoxylated amine or a mixture of ethoxylated amines) may be present in a surfactant composition in an amount of greater than 15% of the surfactants actives by weight, alternatively from 15% to about 50% of the surfactant actives by weight, alternatively from 15% to about 35% of the surfactant actives by weight, alternatively greater than about 16% of the surfactant actives by weight, alternatively from about 16% to about 50% of the surfactant actives by weight, alternatively from about 16% to about 35% of the surfactant actives by weight, alternatively greater than about 17% of the surfactant actives by weight, alternatively from about 17% to about 50% of the surfactant actives by weight, alternatively from about 17% to about 35% of the surfactant actives by weight, alternatively greater than about 18% of the surfactant actives by weight, alternatively from about 18% to about 50% of the surfactant actives by weight, alternatively from about 18% to about 35% of the surfactant actives by weight, alternatively greater than about 19% of the surfactant actives by weight, alternatively from about 19% to about 50% of the surfactant actives by weight, alternatively from about 19% to about 35% of the surfactant actives by weight, alternatively greater than about 20% of the surfactant actives by weight, alternatively from about 20% to about 50% of the surfactant actives by weight, and alternatively from about 20% to about 35% of the surfactant actives by weight.
In separate respective and alternative embodiments, ethoxylated amine (either a single ethoxylated amine or a mixture of ethoxylated amines) may be present in a surfactant composition in an amount of from about x% to about y% of the surfactant actives by weight, where for each respective embodiment the value of x may be selected from the range of values of from 1 to 59 and a corresponding value of y may be selected from the range of values of from 2 to 60, with the proviso that x is less than y for a given embodiment. For example, in an embodiment where x=20 and y=31, a surfactant composition having an amount of ethoxylated amine of from about 20% to about 31% of the surfactant actives by weight would be represented.
Suitable anionic surfactants that may be employed include any anionic surfactant suitable for forming a salt with the ethoxylated amines and/or ethoxylate ether amines disclose herein. Typically, such anionic surfactant may be characterized as having pKa values less than 7. For example, suitable anionic surfactants include, but are not limited to, linear and/or branched chain alkylbenzene sulfonates, alkyl sulfates, ether sulfates, secondary alkyl sulfates, xcex1-olefin sulfonates, phosphate esters, sulfosuccinates, isethionates, carboxylates, etc. Most of these surfactants are typically sold in the form of a sodium salt.
In one exemplary embodiment, one or more alkylbenzene sulfonate/s may be employed as anionic surfactants. In this regard, alkylbenzene sulfonate compounds having varying molecular weights, alkyl chain length and alkyl chain phenyl location combination may be employed. Examples of such compounds may be found in U.S. Pat. No. 3,776,962; U.S. Pat. No. 5,152,933; U.S. Pat. No. 5,167,872; Drazd, Joseph C. and Wilma Gorman, xe2x80x9cFormulating Characteristics of High and Low 2-Phenyl Linear Alkylbenzene Sulfonates in Liquid Detergents,xe2x80x9d JAOCS, 65(3):398404, March 1988; Sweeney, W. A. and A. C. Olson, xe2x80x9cPerformance of Straight-Chain Alkylbenzene Sulfonates (LAS) in Heavy-Duty Detergents,xe2x80x9d JAOCS, 41:815-822, December 1964.; Drazd, Joseph C., xe2x80x9cAn Introduction to Light Duty (Dishwashing) Liquids Part I. Raw Materials,xe2x80x9d Chenlical Times and Trends, 29-58, January 1985; Cohen, L. et al., xe2x80x9cInfluence of 2-Phenyl Alkane and Tetralin Content on Solubility and Viscosity of Linear Alkylbenzene Sulfonate,xe2x80x9d JAOCS, 72(1):115-122, 1995; Smith, Dewey L., xe2x80x9cImpact of Composition on the Performance of Sodium Linear Alkylbenzenesulfonate (NaLAS),xe2x80x9d JAOCS, 74(7):837-845, 1997; van Os, N. M. et al., xe2x80x9cAlkylarenesulphonates: The Effect of Chemical Structure on Physico-chemical Properties,xe2x80x9d Tenside Surif Det., 29(3):175-189, 1992; Moreno, A. et al., xe2x80x9cInfluence of Structure and Counterions on Physicochemical Properties of Linear Alkylbenzene Sulfonates,xe2x80x9d JAOCS, 67(8):547-552, August 1990; Matheson, K. Lee and Ted P. Matson, xe2x80x9cEffect of Carbon Chain and Phenyl Isomer Distribution on Use Properties of Linear Alkylbenzene Sulfonate: A Comparison of xe2x80x98Highxe2x80x99 and xe2x80x98Lowxe2x80x99 2-Phenyl LAS Homologs,xe2x80x9d JAOCS, 60(9):1693-1698, September 1983; Cox, Michael F. and Dewey L. Smith, xe2x80x9cEffect of LAB composition on LAS Performance,xe2x80x9d INFORM, 8(1):19-24, January 1997; U.S. patent application Ser. No. 08/598,692 filed on Feb. 8, 1996, U.S. patent application Ser. No. 09/141,660 filed on Aug. 28, 1998, and U.S. patent application Ser. No. 09/143,177 filed on Aug. 28, 1998; all of the foregoing references being incorporated herein by reference in their entirety.
In one embodiment, alkylbenzene sulfonate compounds used in accordance with the disclosed compositions and methods and having the characteristics described herein include those having a linear alkyl group. Typically linear alkyl chain lengths are between about 8 and about 16 carbon atoms, although greater and lesser lengths are possible.
In the practice of the disclosed method and compositions, an alkylbenzene sulfonate may include any counterion or cation suitable for neutralization. In one embodiment a counterion or cation is typically ammonium or substituted ammonium. In this regard, a substituted ammonium may include, but is not limited to, monoethanol ammonium, diethanol ammonium, triethanol ammonium, or a mixture thereof. In another embodiment, such a counterion or cation may be an alkali metal, an alkaline earth metal, or a mixture thereof. Typical alkali metals include, but are not limited to, lithium, sodium, potassium, cesium, or a mixture thereof. Typical alkaline earth metals include, but are not limited to, magnesium, calcium, strontium, barium, or a mixture thereof.
One specific low 2-phenyl alkylbenzene sulfonate composition is a sulfonate prepared from a linear alkyl benzene known as ALKYLATE225(trademark) (commercially available from Huntsman Specialty Chemicals Corporation). Other examples of suitable linear alkylbenzenes for preparing linear alkyl benzene sulfonates include, but are not limited to, ALKYLATE 215(trademark), ALKYLATE 229(trademark), ALKYLATE H230L(trademark), and ALKYLATE H230H(trademark) (also available from Huntsman Specialty Chemicals Corporation). Suitable processes for sulfonating such linear alkyl benzenes include, but are not limited to, those employing an air/SO3 sulfonator or chlorosulfonic acid.
Examples of other suitable anionic surfactant types include, but are not limited to, alkyl sulfates, ether sulfates, secondary alkyl sulfates, xcex1-olefin sulfonates, xylene sulfonates, alcohol sulfates, phosphate esters, naptbalene sulfonates, sulfosuccinates, isethionates, carboxylates, etc.
Specific examples of other suitable anionic surfactants include, but are not limited to, the surfactants listed in Table 5 and available from Huntsman Corporation, Houston, Tex.
Still other specific examples of suitable anionic surfactants include, but are not limited to, the surfactants listed in Table 6 available from Witco Corporation, Greenwich, Conn.
Still other specific examples of anionic surfactants include, but are not limited to, the surfactants listed in Table 7 and available from Stepan Company.
It will be understood with benefit of this disclosure by those of skill in the art that the foregoing examples of anionic surfactants are exemplary only, and that other anionic surfactants meeting the criteria set forth herein may also be employed.
In one embodiment, an amount of anionic surfactant sufficient to neutralize the ethoxylated amine surfactant is employed, although greater or lesser amounts are also possible.
As described above, embodiments of the disclosed surfactant compositions include anionic surfactants/s blended with ethoxylated amine, ethoxylated ether amine, or mixtures thereof. However, a wide variety of other optional ingredients may also be added if so desired. For example, one or more nonionic surfactant/s may also be added for the purpose of purpose of lowering the mixture viscosity, and without destroying the salt. In this regard, any nonionic surfactant or mixture thereof suitable for lowering the pour point may be employed. In one embodiment, an amount of nonionic surfactant sufficient to dissolve the anionic-ethoxylated amine surfactant is employed, although greater or lesser amounts are also possible.
Examples of suitable nonionic surfactant types include, but are not limited to, nonylphenol ethoxylates, alcohol ethoxylates, ethylene oxide/propylene oxide (xe2x80x9cEOxe2x80x94POxe2x80x9d) block copolymers, and mixtures thereof. Specific examples include, but are not limited to, nonylphenol ethoxylates such as xe2x80x9cSURFONIC N95(trademark)xe2x80x9d available from Huntsman and linear alcohol ethoxylates such as xe2x80x9cSURFONIC L24-7(trademark)xe2x80x9d also available from Huntsman. Other specific examples include, but are not limited to, nonionic surfactants commercially available from Huntsman Corporation and Witco, as described below.
Specific examples of suitable nonionic surfactants available from Huntsman Corporation include, but are not limited to, surfactants listed in Table 8.
Examples of suitable nonionic surfactants also include products available from Witco. Such products include, for example, WITCONOL(trademark) linear ethoxylated alcohols, DESONIC(trademark) alkylphenol ethoxylates, WITCAMIDE(copyright) and VARAMIDE(trademark) amide ether condensates, and VARONIC(trademark) coco and tallow amine ethoxylates. Some specific examples of such surfactants are listed in Table 9. Other nonionic materials include, but are not limited to, alcohol ethoxylates (xe2x80x9cAExe2x80x9d), nonylphenol ethoxylates (xe2x80x9cNPExe2x80x9d), ethoxylated mono and diglycerides, ethoxylated amines, amides, amine oxides and specialty blends.
Specific examples of suitable nonionic surfactants available from Stepan include, but are not limited to, surfactants listed in Table 10.
If desired, neutralization of anionic surfactants in the disclosed surfactant compositions may be accomplished with the addition of a basic compound. Examples of such optional neutralizing compounds include, but are not limited to, alkanolamines, alkyl amines, ammonium hydroxide, NaOH, KOH, and mixtures thereof Amounts of neutralizing compound may be any amount suitable for partially or completely neutralizing an anionic surfactant acid. In one embodiment, an amount of neutralizing compound sufficient to neutralize about 75% of the anionic surfactant is employed, although greater or lesser amounts are also possible. Sufficient alkoxylated amine may be employed in conjunction with the neutralization compound to neutralize about 25% of the anionic surfactant.
In the formulation and practice of the disclosed compositions and methods, a viscosity modifier may be employed suitable to prevent gel phase formation upon dilution. Examples of suitable modifiers compounds include polyethylene glycols, ethylene glycol, propylene glycol, and mixtures thereof Examples of suitable polyethylene glycol compounds include, but are not limited to, polyethylene glycol compounds having a molecular weight of between about 100 and about 1000, alternatively between 200 and about 400. Specific examples include one or more polyethylene glycol solubility enhancers having between about 1 and about 20, alternatively between about 3 and about 6 ethylene glycol monomers joined by ether linkages. Specific examples of such polyethylene glycol compounds include, but are not limited to, polyethylene glycol products marketed by Huntsman Chemical Corporation under the trade name POGOL(trademark), and POGOL 300. In the case of POGOL(trademark) compounds, the numeric designation indicates the average molecular weight of the polyethylene glycol compounds. Specific examples may be found in table 8. In one embodiment, an amount of viscosity modifier compound sufficient to obtain a low viscosity liquid is employed, although greater or lesser amounts are also possible.
The disclosed surfactant compositions may be provided in solid form without a solvent (which, for example, may be combined with a solvent later), or in liquid form with a solvent. In those embodiments employing solvents, any solvent suitable for use in the formulation of a liquid detergent formulation may be employed. Suitable solvents include, for example, those solvents capable of dissolving low 2-phenyl linear alkylbenzene sulfonates. Examples of suitable solvents include, but are not limited to, water, alcohols, glycols and glycol ethers, or mixtures thereof. Specific examples of suitable alcohol solvents include, but are not limited to, alcohols having from about 1 to about 6 carbon atoms. In the practice of the disclosed method and compositions, typical specific solvents include water, straight chain alkyl alcohols containing from one to six carbon atoms (example: methanol, ethanol, n-propanol, n-hexanol, etc.), branched chain alkyl alcohols containing from three to six carbon atoms (example: isopropanol and secondary butanol), glycols such as propylene glycol, diglycols such as propylene diglycol and triglycols such as triethylene glycol and glycol ethers such as butylene glycol diethylether and dipropylene glycol methylether. In one embodiment, an amount of solvent sufficient to obtain a low viscosity liquid is employed, although greater or lesser amounts are also possible.
In one embodiment, by employing propylene glycol a surfactant composition may be formulated to exist as a single or substantially homogenous liquid phase (without segregation) at about 40xc2x0 F. using other components described elsewhere herein, but with substantially no water. In such an embodiment, propylene glycol may be present to substantially prevent separation or segregation of a composition at, for example, ambient temperatures. Such a formulation may be less corrosive than aqueous solutions and may allow shipping of a composition having substantially no excess weight due to water content.
In one particular embodiment, a surfactant concentrate composition may be formulated by blending together the components listed in Table 11.
Although one particular combination of components and weight percentages thereof has been listed in Tables 11, it will be understood with benefit of this disclosure that other combinations, other components as well as other weight percentages (including outside those ranges listed in Table 1), may be employed in the practice of the disclosed compositions.